Conventionally, the image forming apparatus for forming the image with the liquid developer containing the toner and the liquid developer has been known. In the image forming apparatus, the liquid developer which is not used in an image forming step is collected and recycled. In such a recycling process of the liquid developer, toner particles which are a dispersoid in the liquid developer (liquid material) and the carrier liquid which is a dispersion medium in the liquid developer are separated, and then the carrier liquid is used again (for example, Japanese Laid-Open Patent Application 2008-242436).
However, by repeating recycling, in the carrier liquid, a substance having a low volume resistivity accumulates. Thus, a resistance of an entirety of the liquid developer lowers, so that there is a liability that an image defect generates. By periodically exchanging (replacing) a container accommodating the liquid developer, the generation of the image defect can be suppressed, but in this case, a running cost increases, as does a load of maintenance by a user or a service person.